Perhaps you can help me understand. To me, an Almost Hidden Pair solution would be when there is a common outcome if the pair is true and if the "fin" is true. I don't see where the chain reflects an Almost Hidden Pair. Sure, the 1st term of r8c6<>1 is a result of the pair being true but I don't see anything about what happens if the pair is not true. Having said that, I think your solution is clever but don't see it as Almost Hidden Pair solution.

Marty R. wrote: To me, an Almost Hidden Pair solution would be when there is a common outcome if the pair is true and if the "fin" is true.

Marty, I have the same definition, and I guess it is met here:The "fin" is 8r8c6If the pair (78)r16c6 is true, then r1c6<>1, r1c2=1, r3c1=8, r8c1<>8If the fin 8r8c6 is true, then r8c1<>8r8c1<>8 is the common outcome.

Maybe could I have written it clearer this way:(87)r16c6 - (1)r1c6 = r1c2 - (1=8)r3c1(8)r8c6=> -8 r8c1; stte

Marty R. wrote: To me, an Almost Hidden Pair solution would be when there is a common outcome if the pair is true and if the "fin" is true.

Marty, I have the same definition, and I guess it is met here:The "fin" is 8r8c6If the pair (78)r16c6 is true, then r1c6<>1, r1c2=1, r3c1=8, r8c1<>8If the fin 8r8c6 is true, then r8c1<>8r8c1<>8 is the common outcome.

Maybe could I have written it clearer this way:(87)r16c6 - (1)r1c6 = r1c2 - (1=8)r3c1(8)r8c6=> -8 r8c1; stte

I don't want this exchange to go on forever. But we differ on the fin . I think the fin is 1 r1c6 since that precludes a 78 pair. Based on that, if the pair is true then r1c6<>1 and if false r1c6=1 and those can't yield a common outcome. ???

Marty R. wrote:But we differ on the fin . I think the fin is 1 r1c6 since that precludes a 78 pair. Based on that, if the pair is true then r1c6<>1 and if false r1c6=1 and those can't yield a common outcome. ???

Marty,

The term of fin is used in fish patterns. Here, you and I have used it by analogy, but with " ", which is justified since the pattern (78)r16c6 is a pair and not a fish (not even a 1-fish): it cannot work without the 7's.To me, the "fin" is rather 8r6c6, once more by analogy to fish-patterns whose fins are candidates of the same digit as the fish itself.

You focus on the strong link (78=1)r16c6 whereas I focus on the weak link (78-1)r16c6. Both links are true ! Cells r16c6 contains an ALS as well as an AHS (particular case of ALS's with two and only two unlocked digits)If I had used 1r1c6 as the "fin", I would have called the pattern "Almost naked pair". It is feasible and also yields a killing common outcome (-1 r3c1):(78)r16c6 - (1)r1c6 = r3c5 - r3c123 = (1)r1c2(1)r1c6 - (1=8)r89c6 - (8=1)r8c1=> -1 r3c1; stteNote the use of both links of 1r1c6 to the pair (78)r16c6 but chains are a bit longer...